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Finally my amplifier under construction, here are some pics and also a pdf file of the construction of this amplifier.
The amplifier can deliver 700 watts into 8 ohms with a dynamic burst of nearly 1000 watts

Hi Behrad, My amplifier is class AB and stereo. I tested it with dummy load and oscilloscope.
Yesterday I finished assembly and also tried with 4 ohms dummy load and I got 527w per channel (65v peak on 1KHz tone). I also tested with speakers but small ones about 100w power to check for clarity and It has very good sound and very clear. I do not have any kind of noise with no signal and full volume. The power supply handles the amplifier very well. I need to purchase a couple of good 12 or 15 inch 300w 2 way speakers with tweeter horns for it.
In the PDF file I posted in the last post I have more pictures of the amplifier and also described the things I have in it.

I have been trying to repair smps for a while now,some were successful and some ended up in a miniature atom bomb ,lol. reading helps but the best way to understand anything is build it and apply your theory. Safely that is! i will be trying to build the ludo version , i hope i will get some feedback from other diyer's that have built it. Before i forget a BIG THANK YOU to LUDO,MICROSIM and SILVIO . I will keep everyone posted with results as i get on!

Hello Audibrad,
The circuit of LUDO works if followed correctly, All the information is available on this site and it should be a successful build. When you come to wind the transformer for it I will give you details of the windings according to your output voltage needed. You can also follow the blog posts regarding winding practices and pcb clearances for a safe smps.

Hello Silvio,
I finally got hold of a 'scope, it is an old but useful 20MHz. I've been browsing the forum on how to use it in measuring an SMPS. Can you please direct me to a written document if there exists one? I have here a few đocs how to conduct such test, but the mention of a differential/current probe confuses me. My scope does not seem to have the capability to use such probe.

Hello Silvio,
I finally got hold of a 'scope, it is an old but useful 20MHz. I've been browsing the forum on how to use it in measuring an SMPS. Can you please direct me to a written document if there exists one? I have here a few đocs how to conduct such test, but the mention of a differential/current probe confuses me. My scope does not seem to have the capability to use such probe.

@ Abet
A differential current probe is the best to have but it is also costly to purchase one. The best way to handle smps is to have an isolating transformer for your smps which has 220v in and isolated 220v out. At least there will not be any ground paths between YOU, the smps and the scope.

The other option is to have a small isolating transformer that can handle the power of your scope to galvanically isolate it from the mains. You still have to be careful though as if you only have the scope isolated and if the casing of your scope and buttons, switches etc are made of metal you can be electrocuted. Current limit for your smps can be made with a 100w incandescent bulb attached with its wires in series with the smps under test.

I hope you have a X10 test probe to measure with. See also the voltage rating your oscilloscope can handle so that it will not be overloaded. Mine can handle 300v.

You can make your initial test before fitting the transformer on the pcb and using an external DC power supply to power up your pcb at low voltage. This way you can see the wave forms and make sure it is working ok before applying 220v to your smps.

I hope this help you to understand a bit what all involves for safety. SMPS do not joke when they blow and great care must be taken on initial power up until you are sure the smps is stable.

I will help you along as you progress and do not hesitate to ask if you need to know anything. I will give you some more tips tomorrow as it is half past one in the morning and I need to go to sleep.

Thank you for the quick reply, yes my probe do had X10 and are rated 600V 100MHz. I am using an AVR before the AC 220v wall socket and I do use a series connect 100w bulb limiter. I will be waiting for your tutorial write ups with a keen interest, but I may not be able to reply the soonest as I am currently experiencing internet slowdowns here in my place.